Tuesday 29 December 2009 13.23 EST
First published on Tuesday 29 December 2009 13.23 EST

Poland will formally seek Sweden's help in investigating the theft of the Arbeit Macht Frei sign from Auschwitz, confirming that Polish authorities suspect a Swedish link in the crime.

Boguslawa Marcinkowska, a spokeswoman for Krakow prosecutors, said a formal request for help would be sent tomorrow to the Swedish justice ministry in Stockholm.

Polish media have been reporting that the theft was commissioned by a collector living in Sweden, but investigators have yet to confirm that.

The sign, which means "work sets you free," was stolen earlier this month and was found two days later cut into three pieces. Police have arrested five men whom they described as common criminals who likely stole the sign on a commission from abroad.